Contraception Flashcards
What are the different groups of contraceptives?
- Combined Hormonal Contraception (CHC)
- pills, patch, vaginal ring
- Progestogen only methods
- pill, injectable, implant, IUD
- copper Intrauterine Device (IUD)
- emergency contraception
- sterilisation
- barrier method
- condoms, diaphragm
What is The Pearl Index?
The number of contraceptive failures per 100 women-years of exposure.
It looks at total months/cycles of exposure from the initiation of the product to the end of the study.
What is Life Table Analysis?
The contraceptive failure rate over a specified time frame and cumulitive failure rate for any specific length of exposure.
What is meant by;
method failure + user failure?
- method failure- pregnancy depite correct use of method by user
- user failure- pregnancy because method is not used correctly by user
* Long Acting Reversible Contraception (LARC) minimises user input ∴ minimises user failure rates
At what point in the uterine cycle is pregnancy most likely?
- ovulation 12-18 (2 weeks before period)
- egg survives 24hrs + sperm < 4 days
∴ highest chance of pregnancy day 8-19
What hormones are in Combined Hormonal Contraception, what do they do
and how is each method used?
- ethinyl estradiol (EE)
- sythetic progesterone (progestogen)
- stop ovulation, thicken cervical mucous, thin endometrium
- 21 days with hormone free week/tricycling/continuous
- pill- taken daily
- not good if frequent GI upset
- patch (EVRA)- changed weekly
- < 5% have skin reaction
- ring (Nuvaring)- changed every 3 weeks
- can be taken out 3/24hrs
- latex free
What are some non-contraceptive benefits of Combined Hormonal Contraception?
- regulate/reduce bleeding
- stop ovulation (help PMS)
- dec. funtional ovarian cysts
- 50% dec. ovarian + endometrial cancer
- dec. benign breast disease, rheumatoid arthritis, colon cancer, osteoporosis
- improve acne/hirtuism
What are some side effects of Combined Hormonal Contraception?
- breast tenderness
- nausea
- headache
- irregular bleeding (first 3 months)
- effect mood
- weight gain
What are some serious risks of using Combined Hormonal Contraception?
- venous thrombosis (DVT, PE)
- contraindications; BMI > 34, previous VTE, 1st ° relative < 45 VTE, thrombophilia
- arterial thrombosis (MI, ischaemic stroke)
- contraindications; smokers > 35, previous ATE, focal migraine, age > 50, BP > 140/90
- inc. risk cervical cancer
- inc. risk breast cancer
* avoid if active gallbladder disease or previous liver tumour
What does the Progestogen Only Pill (POP/minipill) do and how is it used?
- Desogestrel (12hr window)
- stops ovulation, thickens mucous
- most bleed free
- LGN NET (3hr window)
- 1/3 stops ovulation, thickens mucous
- 1/3 bleed free, 1/3 regular, 1/3 irregular
- pill taken same time every day
- not good if frequent GI upset
What are progestogenic side effects and risks?
- inc. appetite
- hair loss/gain
- mood change
- bloating/retention
- headache
- acne
* avoid if current breast cancer or past/present liver tumour
How is injectable progestogen (the jag) administered and what does it do?
- Depoprovera (depomedroxyprogesterone acetate)
- 150mg 1ml, deep IM injection, upper outer quadrant of buttock, every 13 weeks
- Sayana press
- 0.6ml SC injection, self administered
- prevents ovulation
- thickens mucous
- thins endometrium
What are side effects of injectable progestogen?
- 70% amenorrhoeic affter 3 doses
- irregular bleeding (esp. first 2 doses)
- delay in return to fertility (average 9 months)
- reversible reduction in bone density
- 2/3 women gain 2-3kg
What is the subdermal progestogen implant (the rod) made of and what does it do?
- Nexplanon- etonegestrel ENG (core) + ethinyl vinyl acetate EVA (membrane)
- prevents ovulation
- thickens mucous
* lasts up to 3 years
What are side effects of the subdermal progestogen implant?
- 60% bleed free
- 30% prolonged/frequent bleeding
- most likely to cause mood change, compared to other progestogen only methods
